The Biostatistical and Recruitment Core (formally, Human Assessment and Biostatistics Core) will continue to play an integral role as part of the Special Center of Research in Neurobiology of Sleep and Sleep Apnea. The Core's specific aims (functions) are: 1) to meet the biostatistical needs of the two human study projects and two animal projects providing innovative solutions to data analysis challenges arising from these projects (all projects); 2) to provide centralized statistical programming and data management resources to the human projects (Projects by Weaver and Kuna and; 3) to apply existing methods and to make substantial contributions to the development of optimal statistical methods related to defining phenotypic characteristics associated with genetic control of homeostatic sleep regulation (Projects by Weaver and Kuna; 4) to support database management infrastructure development for the human and animal (all projects); 5) to promote the sound use of statistical principles and experimental design by all SCOR investigators (all projects); and 6) to provide the recruitment infrastructure enabling recruitment of apnea patients (Project by Weaver) and twins (Project by Kuna), the latter to be facilitated through a partnership with an existing twin cohort (PennTwins, E. Coccaro). Core C (Biostatistical and Recruitment Core) is comprised of a very experienced team of biostatisticians, statistical programmers, database managers, and clinical recruitment personnel. There exists a long history of collaboration among Core C staff and between Core C staff and SCOR investigators. The Core Leader of Core C has been SCOR biostatistician since its inception in 1988 and Core Leader since 1990. He has an extensive record of collaboration with SCOR investigators as well as original research in the field of sleep. The Core Leader (Senior Biostatistician) will be assisted by an Associate Biostatistician whose focus will be on providing biostatistical support to the animal studies and who is experienced in applying the mixed effects statistical models appropriate for the experimental designs proposed for these projects. Core C also includes a senior SAS TM statistical programmer with a longtime association with the Core who specializes in the development of analysis systems for implementation of complex statistical models that utilize data from multiple sources, an experienced database manager/statistical programmer with expertise in Access database development, and a data clerk. In addition, the Core Leader will be assisted by an experienced senior clinical study recruiter who will direct the human studies recruitment function, provide liaison with the PennTwins Cohort, and who will be assisted by additional recruitment staff. The experience, scientific interest, and long history of collaboration with SCOR investigators make the Biostatistical and Recruitment Core well-positioned to provide state-of-the-art statistical, database management, and human studies recruitment support to the projects while contributing to the advancement of statistical methods necessary to address the specific aims of the projects.